全文获取类型
收费全文 | 369篇 |
免费 | 6篇 |
专业分类
375篇 |
出版年
2021年 | 7篇 |
2019年 | 7篇 |
2018年 | 4篇 |
2017年 | 3篇 |
2016年 | 7篇 |
2015年 | 2篇 |
2014年 | 5篇 |
2013年 | 55篇 |
2012年 | 3篇 |
2009年 | 4篇 |
2007年 | 12篇 |
2005年 | 2篇 |
2004年 | 3篇 |
2003年 | 7篇 |
2002年 | 6篇 |
2001年 | 2篇 |
2000年 | 3篇 |
1999年 | 3篇 |
1998年 | 7篇 |
1997年 | 8篇 |
1996年 | 9篇 |
1995年 | 3篇 |
1994年 | 6篇 |
1993年 | 10篇 |
1992年 | 7篇 |
1991年 | 9篇 |
1990年 | 10篇 |
1989年 | 17篇 |
1988年 | 14篇 |
1987年 | 7篇 |
1986年 | 13篇 |
1985年 | 7篇 |
1984年 | 4篇 |
1983年 | 3篇 |
1982年 | 10篇 |
1981年 | 6篇 |
1980年 | 7篇 |
1979年 | 9篇 |
1978年 | 8篇 |
1977年 | 5篇 |
1976年 | 5篇 |
1975年 | 4篇 |
1974年 | 8篇 |
1973年 | 5篇 |
1972年 | 3篇 |
1971年 | 7篇 |
1970年 | 6篇 |
1969年 | 5篇 |
1967年 | 6篇 |
1948年 | 4篇 |
排序方式: 共有375条查询结果,搜索用时 0 毫秒
31.
In Turner and Holmes [8] a model for evasive vehicle movement along a fixed track is developed within the mathematical framework of a two-state semi-Markov process. They derive a number of analytical properties of the model. In this article we address problems concerning the estimation of parameters in the model and the construction of data-based prediction equations. 相似文献
32.
33.
34.
35.
36.
We introduce and develop models for a physical goods storage system based on the 15‐puzzle, a classic children's game in which 15 numbered tiles slide within a 4 × 4 grid. The objective of the game is to arrange the tiles in numerical sequence, starting from a random arrangement. For our purposes, the tiles represent totes, pallets, or even containers that must be stored very densely, and the objective is to maneuver items to an input–output point for retrieval or processing. We develop analytical results for storage configurations having a single empty location (as in the game) and experimental results for configurations with multiple empty locations. Designs with many empty locations can be made to form aisles, allowing us to compare puzzle‐based designs with traditional aisle‐based designs found in warehousing systems. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007 相似文献
37.
Hakimi has considered the problem of finding an optimal location for a single service center, such as a hospital or a police station. He used a graph theoretic model to represent the region being serviced. The communities are represented by the nodes while the road network is represented by the ares of the graph. In his work, the objective is one of minimizing the maximum of the shortest distances between the vertices and the service center. In the present work, the region being serviced is represented by a convex polygon and communities are spread over the entire region. The objective is to minimize the maximum of Euclidian distances between the service center and any point in the polygon. Two methods of solution presented are (i) a geometric method, and (ii) a quadratic programming formulation. Of these, the geometric method is simpler and more efficient. It is seen that for a class of problems, the geometric method is well suited and very efficient while the graph theoretic method, in general, will give only approximate solutions in spite of the increased efforts involved. But, for a different class of problems, the graph theoretic approach will be more appropriate while the geometric method will provide only approximate solutions though with ease. Finally, some feasible applications of importance are outlined and a few meaningful extensions are indicated. 相似文献
38.
We study the (s,S) inventory system in which the server takes a rest when the level of the inventory is zero. The demands are assumed to occur for one unit at a time. The interoccurrence times between successive demands, the lead times, and the rest times are assumed to follow general distributions which are mutually independent. Using renewal and convolution techniques we obtain the state transition probabilities. 相似文献
39.
R. A. Beaumont 《Defense & Security Analysis》1988,4(1):115-117
The Cavalry Goes Through. By Bernard Newman. Henry Holt, New York (1930) 相似文献
40.